The present invention relates to a method for manufacturing disk-shaped workpieces using a sputter station for processing the circular workpieces, in particular for depositing reflective coatings on optical storage media subsequently referred to as CDs. The station comprises a lock chamber, a sputtering source with an active surface, as well as a transport chamber with one connection opening respectively to the lock chamber and the sputtering source, designed for passing through or transporting a workpiece into or from a sputtering position. This station also features a transport device in the transport chamber for transporting a workpiece between said openings.
The objective of the present invention is to provide a sputter station method that combines the following advantages in the sputter station:
Smallest possible dimensions and minimal space requirements;
Short cycle times between loading and unloading of a workpiece through the vacuum lock;
Freely selectable installation in any mounting plane, that is, sputtering from the top down, from the bottom up, or horizontally;
Modular installation in an overall sputtering system;
Simple design, robust; and
Low manufacturing and maintenance costs.
In the sputtering station of the aforementioned type these advantages are achieved by arranging the lock chamber and the active surface of the sputtering source mutually opposite across the transport chamber and along a corresponding transverse axis, where the transport device is swivel mounted around an axis of rotation in the transport chamber and is driven for swiveling, said axis being perpendicular to the transverse axis and defines a plane together with said transverse axis, the transport device comprising at least one carrier arm that is radially or parallel extendable or retractable relative to the axis of rotation, where said carrier arm features a workpiece holder at the end opposite the axis of rotation.
In the preferred embodiment said transport device has at least two such arms. The parts of said arm that are movable relative to each other are preferably encapsulated by bellows.
The construction of the station according to the invention is especially simplified in the preferred arrangement, in that the workpiece holder constitutes the lock valve of the lock chamber on the transport chamber side and/or the sealing device between the sputtering source and the transport chamber.
The ability to choose any mounting plane is further improved in a most simple manner in that the workpiece holder features a retaining device for a workpiece, preferably a snap-in retaining device, for disc-shaped workpieces with center hole preferably a spring-loaded ball arrangement that engages in the center hole.
The advantage of the highly compact design is further improved in that the lock chamber is essentially defined by the wall thickness of the transport chamber wall surrounding one of the openings and/or by defining the sputter process chamber essentially by the wall thickness of the transport chamber wall surrounding the other of said openings.
In a preferred embodiment the lock chamber and the transport chamber and/or the process chamber of the sputtering source are each equipped with pump ports and/or vent ports.
If the inventive sputter station is built into a vacuum surface treatment system, an electronic module for controlling and monitoring especially said station is preferably provided. There is further provided an additional transport device that serves the lock chamber from the outside. This additional transport device moves preferably in a plane parallel to the plane of the opening between the transport chamber and lock chamber of the station and preferably constitutes the external lock valve of the lock chamber of the sputter station.